Rotary toothbrush with lip guard



Dec. 5. 1950 D. P. GROVER ROTARY TOOTHBRUSH WITH LIP GUARD Filed Aug.22, 1946 INVENTOR. flwza'ifi 6/0067;

Patented Dec. 5, 1950 UNITED STATES ATENT OFFICE 3 Claims.

This invention relates in general to rotary toothbrushes and inparticularto a type of rotary toothbrush adapted for personal use, asdistinguished from those commonly used by dentists. The invention asdisclosed herein comprises further modified forms of the inventiondisclosed in a division of my co -pending application filed August 17,1946, and bearing Ser. No. 691,273.

Various forms of electrically driven rotary toothbrushes have beendeveloped heretofore, but have found very little favor with the publicin general. One of the disadvantages of the early type of rotarytoothbrush was the absence of any shield partially surrounding thebrushelement, thus causing some of the toothpaste on the brush to bethrown off and splattered about during the rotation of the brush andpermitting the brush to contact the soft inner portions of the mouthcausing irritation thereof.

A later development introduced a shield which extended lengthwise of andpartially surrounded the rotating brush element to prevent suchsplattering and mouth irritation. However, actual usage of this type ofbrush proved unsatisfactory because of the tendency of the lip of theuser to be drawn inwardly against the bristles of the brush and betweenthe bristles and the edge of the shield when the brush was placedagainst the teeth.

I have been able to overcome the disadvantages of these earlier types ofrotary toothbrushes inmy present invention, the principal object ofwhich is to provide an electrically driven rotary toothbrush havingnovel guard means to prevent the lip of the user from being pulled ordrawn inwardly against the bristles of the brush element during rotationthereof.

Another object of the invention is to provide a rotary toothbrush havinga plurality of spaced guards along the length of the brush element andextending between the bristles thereon whereby the lip of the user isprevented. from being pulled or drawn inwardly against the brush duringrotation thereof.

A further object is to provide a rotary toothbrush wherein lip guards inthe form of thin wire members are. located adjacent the brush element tothereby prevent the lip of the user from being drawn inwardlytherea-gainst.

Still another object is to provide a rotary toothbrush wherein a seriesof coiled wire mem hers is spaced throughout the length ofthe brushelement. adjacent thereto whereby the lip of a user is prevented frombeing drawn inwardly against the brush.

A still further and more specific object is to provide a rotarytoothbrush having a shield extending lengthwise of and partiallysurrounding the brush element wherein a series of wire coils are spacedapart along the edges of the shield and adjacent the brush element tothu form. a lip guard.

Still another and specific object is to provide a rotary toothbrushhaving a shield extending lengthwise of and partially surrounding thebrush element wherein a plurality of lip guards in the form of thinwires are supported between the edges of the shield and which are bentdownwardly between the ends thereof to pass below the spindle of thebrush element.

A still further object is to provide a lip guard for a rotary toothbrushWhich. consists of a sin gle coil of wire extending lengthwise of thebrush element and having one end thereof secured to the handle portionwhereby the outer edges of the coiled wire will prevent the lip of auser from being drawn inwardly against the brush.

Other objects and advantages of the invention will become apparent upona reading of the following description taken in conjunction with theaccompanying drawing in which:

Fig. 1 is a fragmentary side elevation of a rotary toothbrush embodyingone form of lip guard; i Fig. 2 is a vertical transverse section takensubstantially along the plane of line 2-2 of Fig. 1;

Fig. 3 is a fragmentary perspective view of the forward end of thehandle portion showing the wire lip guards extending across and betweenthe edges of the shield;

Fig. 4 is a fragmentary side elevation similar to Fig. 1 but showing amodified form of lip guard;

Fig. 5 is a vertical transverse section takensubstantially along theplane of line 55 of. Fig. 4;

Fig. 6-is a fragmentary perspective view of that portion of the deviceshown in Fig. 4;

Fig. '7 is a fragmentary side elevation similar to Figs. 1 and 4 butshowing a still further modified form of lip guard;

Fig. 8 is an end elevation taken substantially along the plane of line88 of Fig. '7 and Fig. 9 is a fragmentary perspective view of that formof the invention shown in Fig. 7.

Briefly described, the invention herein consists primarily in theprovision of guard means against which the lip of the user of the rotarytoothbrush will ordinarily bear during the use thereof to guide ordirect the lip to the outer side of the.

shield and thusprevent the lip from being drawn inwardly between thebrush element and the shield. When the rotary brush is in use and placedagainst the teeth the brush element is usually designed to rotate in amanner to brush the teeth away from the gums, which is considered bydentists as the proper way to brush teeth. In actual practice where nolip guards are present, it has been found that brushes of this characterdisclosed in the prior art have a tendency to pull the lip inwardlyagainst the bristles of the brush, and if a shield is present thetendency is to pull the lip between the brush and the edge of theshield. Serious injury to the lip may not necessarily result, but suchan experience is decidedly unsatisfactory and unpleasant, discouragesfurther use of the device by causing rawness and bleeding of the lip andhas been considered the principal reason for the lack of commercialsuccess of earlier rotary toothbrushes. It will be obvious that numerousspecific forms of guard means may be designed to accomplish the mainpurpose of this invention and several of these'forms have been disclosedherein.

In order to further distinguish the forms of the invention disclosedherein from those illustrated and described in my above referred tocopending application, the lip guards herein are preferably formed ofwire. The term wire as used herein is not intended to limit theinvention to steel or other metallic forms of wire as this term iscommonly understood, since the wire may be formed of thin extrudedplastic material or any other material which may be suitable for thispurpose.

The driving means for rotating the brush element may embody an electricmotor inclosed within the handle portion or it may comprise a flexibleshaft adapted to be connected to the rear end of the handle portion todrive a rotatable shaft within the handle to which the brush element isconnected, as more specifically described in my above referred toco-pending application. The specific form of driving means isunimportant since the invention is primarily directed to the lip guardswhich prevent the lip of a user either from being drawn against therotating brush element or from being drawn inwardly between the edges ofthe shield and the brush element during rotation thereof.

Referring now more specifically to the drawing, and more especially toFigs. 1, 2 and 3, the handle portion may be designated by the numeral 1and may have integral therewith a shield 2 which extends forwardly fromthe lower side thereof and which may have an upstanding forward end 3adapted to support one end of the spindle 4 of the brush element. Thespindle 4 carries or supports bristles 5 which constitute a brushelement. The inner end of the spindle 4 may be suitably connected to arotatable shaft 6 within the handle I which may be caused to rotate byany suitable driving means and carry the brush therewith.

The form of lip guard constitutes a plurality of thin wire members Iwhich extend between the upper edges 8 of the shield 2 and which arecurved upwardly as at 9 at each end thereof and downwardly as at ill inthe center thereof. The downwardly curved or concave center of thesewire guards permit the spindle 4 of the brush element to extend abovethe guard members and thus permit easy removal thereof for cleaning orreplacement. The bristles 5 of the brush element will be free to rotatein the spaces between the wire guards l, and the outer curved endportions 9 of the wire guards provide surfaces against which the lip ofa, user may bear and thus prevent the brush from drawing the lipinwardly between the bristles thereon and the edge of the shield, which,as has been mentioned above, is highly undesirable.

Figs. 4, 5 and 6 disclose a modified form of lip guard which also may beformed of wire. In this form of the invention, I provide a series ofcoils of wire ii spaced apart along each edge 8 of the shield 2. Thesemay be either individual and separate coils, or may be a continuous coilpassing through the edge of the shield. In either event, each coil actsas an individual guard to prevent the lip of a user from being drawninwardly between the edge of the shield and the rotating brush element.By being spaced, it permits the bristles to extend between theindividual guards to insure adequate cleaning of the teeth.

This form of the invention also has the advantage of permitting easyremoval of the brush element, because the individual coils are locatedon each side thereof and present no interference with the brush elementwhen it becomes necessary for its removal either for cleaning orreplacement.

A still further modified form of the invention is disclosed in Figs. 7,8 and 9 wherein the shield 2 may be omitted as such, but may be embodiedor integral with the lip guard. A continuous single coil of wire 52 isprovided and which may be secured at one end 53 thereof directly to theforward end 01" the handle i. The forward end M of the coil may beattached to the forward end of the spindle l of the brush element,whereupon the coil and spindle may mutually support each other. In thiscase, the single coil of wire will extend lengthwise of the brushelement and will preferably surround the spindle :3 as clearly shown inFig. 7. The spaces between the individual coils will permit passage ofthe bristles 5 therethrough for cleaning the teeth, and the curvedsurfaces of the coil on each side of the brush element will act as guardmeans preventing the lip of the user from being drawn inwardly againstthe bristles of the brush. The coil of wire itself extends below thebrush element and acts as a shield to prevent the bristles fromcontacting the inner soft portions of the mouth when that side of thebrush is exposed thereto. When it is desired to move the brush element,it is merely necessary to disconnect its forward end from the end i l ofthe coil of wire, at which time it can be merely lifted out.

From the foregoing description it will be evident that I have provided anovel improvement in lip guards for use on rotary toothbrushes whereinthe lip of a user is prevented from being drawn inwardly against thebrush or between the shield and the brush during rotation thereof. Itwill be clear that changes from the specific form of wire lip guardsdisclosed herein may be made without in any way departing from thespirit of the invention or sacrificing any of the attendant advantagesthereof, provided,. however, that such changes fall within the scope ofthe claims appended hereto.

Having thus described my invention what I claim as new and desire tosecure by Letters Pa ent of the United States is:

l. A rotary toothbrush of the class described, comprising a handleportion, a brush element rotatably mounted at one end of said handleportion, guard supporting means having sides extending lengthwise ofsaid brush element, and thin wire guard means having curved portions atboth sides of said brush element and spaced apart throughout the lengththereof, a part of the curvature of each portion being generallyparallel to the periphery of said brush element to prevent the lip of auser from being drawn inwardly against said brush element duringrotation thereof.

2. A rotary toothbrush of the class described, comprising a, handleportion, a brush element rotatably mounted on a spindle at one end ofsaid handle portion, guard supporting means having sides extendinglengthwise of said brush element, and a plurality of wire guard membersextending transversely of said brush element between the sides of saidsupporting means and between said spindle and said supporting means andspaced apart throughout the length thereof, whereby by the bristles ofsaid brush element may extend between said members, and the ends of saidmembers will prevent the lip of a user from being drawn inwardly betweenthe sides of said supporting means and said brush element duringrotation thereof.

3. A rotary toothbrush of the class described, comprising a handleportion, a brush element rotatably mounted at one end of said handleportion, a shield having edges extending lengthwise of said brushelement, said shield partially surrounding said brush element, and aseries of spaced coils of wire mounted on each of the 1ongitudinal edgesof said shield to thereby prevent the lip of a user from being drawninwardly between the edges of said shield and the brush element duringrotation thereof.

DONALD P. GROVER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 559,673 Cafferty May 5, 1896974,304 Spangler Nov. 1, 1919 985,521 Fromm Feb. 28, 1911 1,381,553Hildreth et al June 14, 1921 1,517,917 Murdock Dec. 2, 1924 1,822,631Roig' Sept. 8, 931 1,848,731 Langer Mar. 8, 1932 2,209,647 Elkins et alJuly 30, 1940 2,239,762 Taylor Apr. 29, 1941 2,379,049 Tompkins June 26,1945 FOREIGN PATENTS Number Country Date 676,771 France Nov. 29, 1929

